| pubmed-article:1373789 | pubmed:abstractText | Effect of galanin and CCK8 were studied on isolated smooth muscle cells obtained from pig, guinea-pig, rat, rabbit and dog ileum circular muscle layer. Galanin as well as CCK8 induced a concentration-dependent contraction of pig, rat, rabbit and guinea-pig ileum smooth muscle cells. Maximal contraction ranged between 23.7 +/- 1.9% and 26.1 +/- 3.1% decrease in cell length from control in the presence of both peptides. This maximal contraction was obtained at 1 nM galanin in pig, rat, rabbit, 1 nM CCK8 in rat, rabbit, guinea-pig, at 10 nM galanin in guinea-pig and 10 nM CCK8 in pig. Concentrations of galanin inducing a half maximal contraction (EC50) ranged between 8 pM and 80 pM in these species. In dog, CCK8 induced a concentration-dependent contraction of ileum smooth muscle cells, with a maximal contraction (24.5 +/- 2.3%) at 1nM and an EC50 of 50 pM while galanin inhibited cell contraction induced by CCK8. The CCK-induced contraction was abolished at 10 nM galanin and 10 nM VIP. Concentrations of galanin and VIP inducing a half-maximal relaxation of contracted cells were 2 pM and 3 pM respectively. It is concluded that galanin may induce cell contraction of pig, guinea-pig, rat and rabbit ileum circular muscle layer and cell relaxation of dog ileum by a direct myogenic effect. | lld:pubmed |
